diff --git a/src/Pure/Admin/build_e.scala b/src/Pure/Admin/build_e.scala
--- a/src/Pure/Admin/build_e.scala
+++ b/src/Pure/Admin/build_e.scala
@@ -1,184 +1,184 @@
 /*  Title:      Pure/Admin/build_e.scala
     Author:     Makarius
 
 Build Isabelle E prover component from official downloads.
 */
 
 package isabelle
 
 
 object Build_E
 {
   /* build E prover */
 
   val default_version = "2.5"
 
   val default_download_url =
     "https://wwwlehre.dhbw-stuttgart.de/~sschulz/WORK/E_DOWNLOAD"
 
   val default_runepar_url =
     "https://raw.githubusercontent.com/JUrban/MPTP2/66f03e5b6df8/MaLARea/bin/runepar.pl"
 
   def build_e(
     version: String = default_version,
     download_url: String = default_download_url,
     runepar_url: String = default_runepar_url,
     verbose: Boolean = false,
     progress: Progress = new Progress,
     target_dir: Path = Path.current)
   {
     Isabelle_System.with_tmp_dir("e")(tmp_dir =>
     {
       /* component */
 
       val component_name = "e-" + version
       val component_dir = target_dir + Path.basic(component_name)
       if (component_dir.is_dir) error("Component directory already exists: " + component_dir)
       else {
         progress.echo("Component " + component_dir)
         Isabelle_System.mkdirs(component_dir)
       }
 
       val platform_name =
         proper_string(Isabelle_System.getenv("ISABELLE_PLATFORM64"))
           .getOrElse(error("No 64bit platform"))
 
       val platform_dir = component_dir + Path.basic(platform_name)
       Isabelle_System.mkdirs(platform_dir)
 
 
       /* runepar.pl */
 
       val runepar_path = platform_dir + Path.basic("runepar.pl")
       Isabelle_System.download(runepar_url, runepar_path, progress = progress)
 
       File.write(runepar_path,
         File.read(runepar_path)
           .replace("#!/usr/bin/perl", "#!/usr/bin/env perl")
           .replace("bin/eprover", "$ENV{E_HOME}/eprover")
           .replace("bin/eproof", "$ENV{E_HOME}/eproof"))
 
       File.set_executable(runepar_path, true)
 
 
       /* download source */
 
       val e_url = download_url + "/V_" + version + "/E.tgz"
       val e_path = tmp_dir + Path.explode("E.tgz")
       Isabelle_System.download(e_url, e_path, progress = progress)
 
       Isabelle_System.bash("tar xzf " + e_path, cwd = tmp_dir.file).check
       Isabelle_System.bash("tar xzf " + e_path + " && mv E src", cwd = component_dir.file).check
 
 
       /* build */
 
       progress.echo("Building E prover ...")
 
       val build_dir = tmp_dir + Path.basic("E")
       val build_options =
       {
         val result = Isabelle_System.bash("./configure --help", cwd = build_dir.file)
         if (result.check.out.containsSlice("--enable-ho")) " --enable-ho" else ""
       }
 
       val build_script = "./configure" + build_options + " && make"
       Isabelle_System.bash(build_script,
         cwd = build_dir.file,
         progress_stdout = progress.echo_if(verbose, _),
         progress_stderr = progress.echo_if(verbose, _)).check
 
 
       /* install */
 
       File.copy(build_dir + Path.basic("COPYING"), component_dir + Path.basic("LICENSE"))
 
       val install_files = List("epclextract", "eproof_ram", "eprover", "eprover-ho")
       for (name <- install_files ::: install_files.map(_ + ".exe")) {
         val path = build_dir + Path.basic("PROVER") + Path.basic(name)
         if (path.is_file) File.copy(path, platform_dir)
       }
       Isabelle_System.bash("if [ -f eprover-ho ]; then mv eprover-ho eprover; fi",
         cwd = platform_dir.file).check
 
       val eproof_ram = platform_dir + Path.basic("eproof_ram")
       if (eproof_ram.is_file) {
         File.write(eproof_ram,
           File.read(eproof_ram)
             .replace("EXECPATH=.", "EXECPATH=`dirname \"$0\"`"))
       }
 
 
       /* settings */
 
       val etc_dir = component_dir + Path.basic("etc")
       Isabelle_System.mkdirs(etc_dir)
       File.write(etc_dir + Path.basic("settings"),
         """# -*- shell-script -*- :mode=shellscript:
 
 E_HOME="$COMPONENT/$ISABELLE_PLATFORM64"
 E_VERSION=""" + quote(version) + """
 """)
 
       /* README */
 
       File.write(component_dir + Path.basic("README"),
         "This is E prover " + version + " from\n" + e_url + """
 
 The distribution has been built like this:
 
     cd src && """ + build_script + """
 
 Only a few executables from PROVERS/ have been moved to the platform-specific
 Isabelle component directory: x86_64-linux etc.
 
 This includes a copy of Josef Urban's "runepar.pl" script, modified to use
 the correct path.
 
 
     Makarius
     """ + Date.Format.date(Date.now()) + "\n")
     })
 }
 
   /* Isabelle tool wrapper */
 
   val isabelle_tool =
     Isabelle_Tool("build_e", "build Isabelle E prover component from official download",
     args =>
     {
       var download_url = default_download_url
       var target_dir = Path.current
       var runepar_url = default_runepar_url
       var version = default_version
       var verbose = false
 
       val getopts = Getopts("""
-Usage: isabelle build_e [OPTIONS] DOWNLOAD
+Usage: isabelle build_e [OPTIONS]
 
   Options are:
     -E URL       E prover download URL
                  (default: """ + default_download_url + """)
     -D DIR       target directory (default ".")
     -R URL       URL for runepar.pl by Josef Urban
                  (default: """ + default_runepar_url + """)
     -V VERSION   E prover version (default: """ + default_version + """)
     -v           verbose
 
   Build E prover component from the specified download URLs and version.
 """,
         "E:" -> (arg => download_url = arg),
         "D:" -> (arg => target_dir = Path.explode(arg)),
         "R:" -> (arg => runepar_url = arg),
         "V:" -> (arg => version = arg),
         "v" -> (_ => verbose = true))
 
       val more_args = getopts(args)
       if (more_args.nonEmpty) getopts.usage()
 
       val progress = new Console_Progress()
 
       build_e(version = version, download_url = download_url, runepar_url = runepar_url,
         verbose = verbose, progress = progress, target_dir = target_dir)
     })
 }